Consumers are attracted to crowds in stores, but they are not likely to buy something from a crowded location, according to a new study in the Journal of Consumer Research.

Authors Sam K. Hui (New York University), Eric T. Bradlow, and Peter S. Fader (both University of Pennsylvania) analyzed tracking data from an electronic system called Pathtracker(R), a device attached to the bottom of a shopping cart that emits a signal every five seconds to track shoppers’ paths. They matched the shopping cart paths with purchase records obtained from scanners to create complete records of consumers’ shopping trips. The data came from a large supermarket in the eastern United States.

The data showed that although consumers are attracted to crowded store zones, they are less likely to make a purchase once they arrive.

The authors also discovered that the more time people spend in a store, the more purposeful they become. “As consumers spend more time in the store, they begin to feel time pressure when making the visit. Thus they adapt by changing their shopping strategies: They are less likely to spend time on exploration, and instead focus on visiting and shopping at store zones that carry categories they plan to buy,” write the authors.

The researchers also confirmed a hypothesis posed by earlier researchers that after purchasing a “virtue” product (like a healthy food), people are more likely to purchase something from a “vice” category (like an unhealthy snack).

This study provides field support for hypotheses and theories that were previously tested only in laboratory environments, the authors write. “This offers new insights about actual shopping behavior.”

In the end, the findings may help retailers and designers understand more about consumers’ shopping experiences. “Using our integrated model of consumer behavior, retailers can experiment with different store layouts and product placement schemes by simulating consumers’ paths and purchases,” the authors conclude.